Production of commercially-pure nitrates.



G. BSCH & W. WILD. PRODUCTION 0F GOMMERGIALLY 'PURE NITRATES,

APPLICATION FILED JUNE z2, 1909.

Patentm @et 277 @mi f1/Lema o www mf@ @am CARL BUSCH .AND VYILHEIM WLD, F LUDW'XGSHAFEN-GN-TH-RHINE, GERMANY, SSIGNGRS, BY MESNT SSXGNMENTS, TO NURSE, .T YDRG-LELEKTRISK KVAELSTF- KTESELSKE, 0?? GI-i/STNI. 'NORWAY.

RODUCTION OTE CQMMERCILLY-PURE NITRATS.

Specification of Letters Patent.

Patented. ct. 2l?, Mille?.

- yAggplicstiolri filed June 22, i999. Serial No. 503,638.

To all Mio/niy it may concer?" ide it known that ive, CARL Biiisoii and liLi-ncmr Evian. doctors of philosophy and chemists, subjects, respectively, oi? the King of Prussia sud the Grand Duke of Baden,

. of commercially pure nitrates by direct el sorptioo of oxide of nitrogen by menos of e hotdry absorbent.

The method hitherto adopted of produc mixtures coiitsiniu oxide of nitrogen, such ss are produced, roi* instance., hy treating air is su electric src iaime, has consisted Yiii treating the said mixtures with Water, thus obtaining e diluteA solution of 'nitric acid, and then. neutrslising this dilute scid with e hase, such for' instance os sodo or iime. i direct absorption of. the oizids of nitrogen by o hase has hitherto lcd to miro tures of nitrate sud nitrite.

We have discovered that commercially pure nitrate can loc obtained, if limited quantities of Water vapor be added to the gaseous mixtures containing the oxide of nitrogen and the gases thus treated he then passed over solid basic substances, such as the o Xids, hydroxids, and carbonatos of the slimline 4`earth metals, While maintaining these nt such e temperature that. the water set free :during the .combination of the 'gaseous riitiic acid with the hase remains in the state oi`i`vspor. The tcm )erstere should not he above about 300 i., since otherwise the compound iormedis liable in the presence of moisture to melt, :ind thus cover up lthe remainder of thc shsorhing iusterisl und prevent the proper vfurther' ubsorptiorL` from taking place. instead of treating; the gases =With steam, inely 'divided Water con he added, but it is preferred that the final tenipeitoiure of the shall. he shove the hon ng* point of nitric acid, es then no liqui` nitric scid separates out and, in consequence, metallic vessels can he employed. Aftershe secos mixture containing oxide ci nitrogenhas Vbeen treated with stemmer wuter,ns store ing commercially fpure miti-stes from ges- `site temperature vduets ci? said, it contains nitric scid, either es such, or in .1 state of dissociation, butthis latter state is not disadvantageous, since in either case the subsequent absorption takes place very rapidly :md leads to the vproduction of practically pure nitrate.

The drawing accompanying this speciication represents in vertical section an apL pzustus suitable for carrying out our in vention.

in this apparatus the gases pass through the pipe A while the necessary quantity of steam or Water vapor is allowed to enter through the pipe B and the vslve C,the miX- ture being then led into the vessel D, which contains the absorbent material EE, (for instance lime) resting on s.. grating l?. The gases pass downward through the absorbing materiel and then upward by means of the' pipe iir into c second similar vessel. We prefer to employ o. number osuch vesseis, for instance eight, situated one after the other in series. Each vessel should of course he so constructed that the contents thereof con. be easily removed -and renewed es soon es they l.ire suiiiciently saturated 'with the nitrous gases. The whole series of vessels is preferably embedded in heat-insulating materiel. so thst the heat is couserved as much las ossihle, and therequior carrying out, the process is maintained.

K, K sreopeningsfor introducing the el sorbiiig materiel sind L, L are openings for removing the resulting product.

The following exemple will serve to illustrote further thenature of our invention, but We desire to emphasize perticulorly the fact that this example' is only illustra-tive of methods of carrying out om' invention, and

the invention is in no Why Whatever confined to the example; given.

. 'izlxamplee Pass hotl frases containing two y per cent. oflhitric oxid throughsI compsrstively large, reaction. chamber and during the passage add so much steam or finely divided Writer that eechcubic meter of the gases leaving the reaction chamber contains about Atwenty grams or more ofvmtcrf Then y pass these gases at a temperature of about two hundred degrees centigrsde over brislnlied lime. The gaseous nitric scid which has been formed is slisorhed with great evidity and after a few days a productl containing over ten per cent. of nitrogen is produced. i

Now what We claim isz- 1. The process of producing commercially Anuire nitrate from gases containing oxids of nitrogen Which consists in adding limited quantities of water to the Agases and then bringing them into Contact with an oxygen compound of the alkaline earth series While maintaining a temperature about 280 C. to about 300 C. that the water set free during the absorption remains inthe gaseous state substantially as hereinbefore described.

Q. The process of producing commercially pure calcium nitrate from gases containi CARL BOSCH.

WILHELM WILD.

Witnesses: ERNEST G. EHRHARDT, J. Anno. LLoYD. 

